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Flattening a loft surface

john_fringsjohn_frings Member Posts: 3
So I experimented with modeling a plywood hull for a small boat:


Basically what I want to achieve is to make plans for sawing parts from flat plywood sheets so that they can be curved into the shapes of the model in the link above.

As far as I have understood from other posts on this forum, there is no functionality in onshape to flatten parts that are curved in 3 dimensions.

Is there any plans to add "unfolding" for these types of surfaces to onshape in the future?

Does anyone have a process to do this using some other tool (I'm thinking exporting a part from onshape, flattening it and import the flattened part back to onshape)?
Perhaps there is some math trick to calculate an approximation of the flat shape from the curved part?



  • S1monS1mon Member Posts: 2,216 PRO
    Rhino's smash command or Exactflat are two options. Otherwise you would need to manually divide the surfaces into a bunch of triangles and use the sheetmetal tools to flatten a rougher approximation.
  • 7Cs7Cs Member Posts: 7
    S1mon´s advice is right. I made the hull in Rhino and all te rest in Onshape. The only downside is that Rhino its not free and it is local ( you can crack if know how to do... but its too much work). I Hope OnShape one day get this function. Than we will have a free ultimate CAD software that can plan a boat from ground up ( on a hobbiest level). 
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